Orana taking on Samburu would definitely be of benefit to Hamilton Zoo. Like you say, they’re at capacity and urgently need to shift him on.
The South African import isn’t far away and I imagine Orana’s preference is receive a founder bull and at least one cow to restart their herd. A mature bull would give better chances for breeding results than the adolescent Samburu and an additional cow would supplement the female herd which has been reduced to a single viable cow.
Long term, Orana would want a second bull to act as a stimulant bull. This probably wouldn’t be needed initially with multiple founder bulls imported soon; but following the transfer of the surplus to Australia, either the retention of a second founder bull or the son of the first founder bull would be likely imo.